AIM: To investigate the effects and mechanisms of sphingosine-1-phosphate receptor-2( S1P2R)on lipopolysaccharide( LPS)-induced acute lung injury( ALI). METHODS: ALI model was induced by intratracheal administration of LPS in both wild-type mice and S1P2R-deficient mice. The pathological changes in the lung tissues were observed,and the protein concentration,total cell number,neutrophil ratio,TNF-α level and IL-6 level were determined in the bronchoalveolar lavage fluid( BALF) 24 h after LPS injection. In o...